Main Variables poulation
Total biomass
Data used en both (spatial and No spatial models)
Respecto a los valores y parametros biologicos modelados, los siguientes graficos identifican los estimadores puntuales del recurso
## [1] 16
In a simple way, the core of Stock Synthesis is its population dynamics model, which represents the dynamics of krill populations over time. This model incorporates key biological, environmental and predator data sources. The model is typically formulated using mathematical equations that describe how these parameters interact to determine the abundance and distribution of krill in the study area.
Stock Synthesis v.3.30.21 is a widely used software tool for assessing fish and invertebrate populations, including krill (Euphausia superba) in the Antarctic Peninsula region. The methodology employed by Stock Synthesis involves a comprehensive and integrated approach, utilizing various data sources and modeling techniques to estimate the main population variables of krill in WAP.
The stock assesment model was configured using Stock Synthesis (SS3
hereafter)SS3
(Richard Donald
Methot et al., 2020; Richard D. Methot
& Wetzel, 2013) with the most updated version
(V.3.30.21). SS3 is a structured age and size stock evaluation model, in
the class of models called “Integrated stock evaluation analysis
model”. SS3 has a stock population sub-model that simulates growth,
maturity, fecundity, recruitment, movement, and mortality processes, and
observation sub-models and expected values for different types of data.
The model is coded in C++ with estimation parameters
enabled by automatic differentiation (ADMB) (Fournier et al., 2012; Richard D. Methot & Wetzel, 2013).
The analysis of results and outputs uses R tools and the graphical
interface of the r4ss and ss3diags library (Taylor, 2019; Winker et al., 2024).
By integrating data from multiple sources and considering spatial heterogeneity, the assessment methodology using Stock Synthesis v.3.30.21 provides a robust framework for evaluating the status of krill populations in the Antarctic Peninsula region. This information is essential for supporting management decisions aimed at ensuring the sustainable use of krill resources in this ecologically sensitive area.
read files
In Table 1 we have ten scenarios to test different option in modeling about main consideration in assessment of krill population.
| Scenario | Description |
|---|---|
| s01 | Fishery and Survey (AMLR) data, Predator, Environmental aggregate data in 48.1 |
| s1 | Fishery and Survey (AMLR) data Length, Index, Catch by strata. Predator and Env data |
| s2 | “s1” without S-R relation |
| s3 | “s1” BH S-R relation weak (0.9 steepness) |
| s4 | “s1” BH S-R relation strong (0.6 steepness) |
| s5 | “s1” BH S-R relation mid-strong estimated |
| s6 | “s1” Ricker S-R relation estimated |
| s7 | “s1” w/ set of parameters estimated in (EMM-204/32?) |
Read outputs
Total biomass
Data used en both (spatial and No spatial models)
Respecto a los valores y parametros biologicos modelados, los siguientes graficos identifican los estimadores puntuales del recurso
Step to do a good practice in model diagnosis is;
1. Convergence. Final convergence criteria is 1.0e-042. Residual (visual and metrics)3. Retrospective analysis (Mhon Parameter)all this framework try to follow recommendations of Carvalho et al. (2021)
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERY 0.709 Passed -0.2430108 0.2430108 len
## 2 SURVEY1 0.254 Passed -0.2548105 0.2548105 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.500 Passed -0.1816665 0.1816665 len
## 2 FISHERYEI 0.145 Passed -0.2319052 0.2319052 len
## 3 FISHERYGS 0.338 Passed -0.1813394 0.1813394 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.406 Passed -0.1476043 0.1476043 len
## 6 SURVEYBS 0.189 Passed -0.2452391 0.2452391 len
## 7 SURVEYEI 0.148 Passed -0.2482065 0.2482065 len
## 8 SURVEYGS 0.334 Passed -0.3723597 0.3723597 len
## 9 SURVEYJOIN 0.500 Passed -0.5749614 0.5749614 len
## 10 PREDATOR 0.599 Passed -0.3154527 0.3154527 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.500 Passed -0.1749806 0.1749806 len
## 2 FISHERYEI 0.145 Passed -0.2305068 0.2305068 len
## 3 FISHERYGS 0.179 Passed -0.1714212 0.1714212 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.451 Passed -0.1443901 0.1443901 len
## 6 SURVEYBS 0.500 Passed -0.2456727 0.2456727 len
## 7 SURVEYEI 0.148 Passed -0.2462956 0.2462956 len
## 8 SURVEYGS 0.270 Passed -0.3662464 0.3662464 len
## 9 SURVEYJOIN 0.500 Passed -0.5589689 0.5589689 len
## 10 PREDATOR 0.662 Passed -0.3149107 0.3149107 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.500 Passed -0.1818845 0.1818845 len
## 2 FISHERYEI 0.145 Passed -0.2318971 0.2318971 len
## 3 FISHERYGS 0.338 Passed -0.1816864 0.1816864 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.406 Passed -0.1476270 0.1476270 len
## 6 SURVEYBS 0.189 Passed -0.2453130 0.2453130 len
## 7 SURVEYEI 0.148 Passed -0.2482887 0.2482887 len
## 8 SURVEYGS 0.334 Passed -0.3725888 0.3725888 len
## 9 SURVEYJOIN 0.500 Passed -0.5752936 0.5752936 len
## 10 PREDATOR 0.599 Passed -0.3153551 0.3153551 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.500 Passed -0.1737353 0.1737353 len
## 2 FISHERYEI 0.145 Passed -0.2304893 0.2304893 len
## 3 FISHERYGS 0.179 Passed -0.1694860 0.1694860 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.451 Passed -0.1441670 0.1441670 len
## 6 SURVEYBS 0.500 Passed -0.2450065 0.2450065 len
## 7 SURVEYEI 0.148 Passed -0.2456669 0.2456669 len
## 8 SURVEYGS 0.270 Passed -0.3646529 0.3646529 len
## 9 SURVEYJOIN 0.500 Passed -0.5565613 0.5565613 len
## 10 PREDATOR 0.599 Passed -0.3158392 0.3158392 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.842 Passed -0.1765162 0.1765162 len
## 2 FISHERYEI 0.145 Passed -0.2325618 0.2325618 len
## 3 FISHERYGS 0.338 Passed -0.1688385 0.1688385 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.451 Passed -0.1476926 0.1476926 len
## 6 SURVEYBS 0.189 Passed -0.2403031 0.2403031 len
## 7 SURVEYEI 0.148 Passed -0.2460309 0.2460309 len
## 8 SURVEYGS 0.270 Passed -0.3664355 0.3664355 len
## 9 SURVEYJOIN 0.500 Passed -0.5667153 0.5667153 len
## 10 PREDATOR 0.662 Passed -0.3085015 0.3085015 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.842 Passed -0.1596431 0.1596431 len
## 2 FISHERYEI 0.013 Failed -0.2265191 0.2265191 len
## 3 FISHERYGS 0.338 Passed -0.1506492 0.1506492 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.451 Passed -0.1386304 0.1386304 len
## 6 SURVEYBS 0.500 Passed -0.2364697 0.2364697 len
## 7 SURVEYEI 0.415 Passed -0.2343651 0.2343651 len
## 8 SURVEYGS 0.270 Passed -0.3349930 0.3349930 len
## 9 SURVEYJOIN 0.500 Passed -0.5078385 0.5078385 len
## 10 PREDATOR 0.662 Passed -0.3134572 0.3134572 len
##
## Running Runs Test Diagnosics for Mean length
## Plotting Residual Runs Tests
##
## Runs Test stats by Mean length:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.842 Passed -0.1633150 0.1633150 len
## 2 FISHERYEI 0.013 Failed -0.2266033 0.2266033 len
## 3 FISHERYGS 0.179 Passed -0.1545744 0.1545744 len
## 4 FISHERYJOIN NA Excluded NA NA len
## 5 FISHERYSSIW 0.451 Passed -0.1390665 0.1390665 len
## 6 SURVEYBS 0.500 Passed -0.2401749 0.2401749 len
## 7 SURVEYEI 0.415 Passed -0.2367449 0.2367449 len
## 8 SURVEYGS 0.270 Passed -0.3409538 0.3409538 len
## 9 SURVEYJOIN 0.500 Passed -0.5164933 0.5164933 len
## 10 PREDATOR 0.662 Passed -0.3120771 0.3120771 len
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERY 0.010 Failed -0.8900613 0.8900613 cpue
## 2 SURVEY1 0.210 Passed -2.2028219 2.2028219 cpue
## 3 PREDATOR 0.016 Failed -0.6844772 0.6844772 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.8521502 0.8521502 cpue
## 2 FISHERYEI 0.179 Passed -1.1048793 1.1048793 cpue
## 3 FISHERYGS 0.018 Failed -1.9450662 1.9450662 cpue
## 4 FISHERYJOIN 0.819 Passed -1.9136749 1.9136749 cpue
## 5 FISHERYSSIW 0.025 Failed -0.5893074 0.5893074 cpue
## 6 SURVEYBS 0.278 Passed -2.8964975 2.8964975 cpue
## 7 SURVEYEI 0.708 Passed -2.5384240 2.5384240 cpue
## 8 SURVEYGS 0.753 Passed -3.2473271 3.2473271 cpue
## 9 SURVEYJOIN 0.268 Passed -2.6879570 2.6879570 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.8485654 0.8485654 cpue
## 2 FISHERYEI 0.179 Passed -1.0976764 1.0976764 cpue
## 3 FISHERYGS 0.018 Failed -1.9477457 1.9477457 cpue
## 4 FISHERYJOIN 0.819 Passed -1.8811922 1.8811922 cpue
## 5 FISHERYSSIW 0.025 Failed -0.7126518 0.7126518 cpue
## 6 SURVEYBS 0.278 Passed -2.9021286 2.9021286 cpue
## 7 SURVEYEI 0.708 Passed -2.5417802 2.5417802 cpue
## 8 SURVEYGS 0.753 Passed -3.2584102 3.2584102 cpue
## 9 SURVEYJOIN 0.268 Passed -2.7096152 2.7096152 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.8518535 0.8518535 cpue
## 2 FISHERYEI 0.189 Passed -1.1052789 1.1052789 cpue
## 3 FISHERYGS 0.018 Failed -1.9441438 1.9441438 cpue
## 4 FISHERYJOIN 0.819 Passed -1.9225843 1.9225843 cpue
## 5 FISHERYSSIW 0.278 Passed -0.5881417 0.5881417 cpue
## 6 SURVEYBS 0.278 Passed -2.8966238 2.8966238 cpue
## 7 SURVEYEI 0.708 Passed -2.5402281 2.5402281 cpue
## 8 SURVEYGS 0.753 Passed -3.2458944 3.2458944 cpue
## 9 SURVEYJOIN 0.223 Passed -2.6801077 2.6801077 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.8504505 0.8504505 cpue
## 2 FISHERYEI 0.338 Passed -1.0946586 1.0946586 cpue
## 3 FISHERYGS 0.018 Failed -1.9625822 1.9625822 cpue
## 4 FISHERYJOIN 0.819 Passed -1.8235141 1.8235141 cpue
## 5 FISHERYSSIW 0.025 Failed -0.7196705 0.7196705 cpue
## 6 SURVEYBS 0.278 Passed -2.9002439 2.9002439 cpue
## 7 SURVEYEI 0.708 Passed -2.5269653 2.5269653 cpue
## 8 SURVEYGS 0.753 Passed -3.2701935 3.2701935 cpue
## 9 SURVEYJOIN 0.268 Passed -2.7696303 2.7696303 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.9823692 0.9823692 cpue
## 2 FISHERYEI 0.338 Passed -1.1092727 1.1092727 cpue
## 3 FISHERYGS 0.014 Failed -2.2121292 2.2121292 cpue
## 4 FISHERYJOIN 0.921 Passed -1.5290698 1.5290698 cpue
## 5 FISHERYSSIW 0.133 Passed -0.9503127 0.9503127 cpue
## 6 SURVEYBS 0.118 Passed -3.0527981 3.0527981 cpue
## 7 SURVEYEI 0.314 Passed -2.7301363 2.7301363 cpue
## 8 SURVEYGS 0.148 Passed -3.4204450 3.4204450 cpue
## 9 SURVEYJOIN 0.268 Passed -3.3686127 3.3686127 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.008 Failed -0.9309271 0.9309271 cpue
## 2 FISHERYEI 0.323 Passed -1.0608336 1.0608336 cpue
## 3 FISHERYGS 0.014 Failed -2.1241689 2.1241689 cpue
## 4 FISHERYJOIN 0.819 Passed -1.5195611 1.5195611 cpue
## 5 FISHERYSSIW 0.022 Failed -0.9333423 0.9333423 cpue
## 6 SURVEYBS 0.333 Passed -2.9855109 2.9855109 cpue
## 7 SURVEYEI 0.314 Passed -2.5966236 2.5966236 cpue
## 8 SURVEYGS 0.148 Passed -3.4016378 3.4016378 cpue
## 9 SURVEYJOIN 0.268 Passed -3.1479524 3.1479524 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.002 Failed -0.7168626 0.7168626 cpue
##
## Running Runs Test Diagnosics for Index
## Plotting Residual Runs Tests
##
## Runs Test stats by Index:
## Index runs.p test sigma3.lo sigma3.hi type
## 1 FISHERYBS 0.010 Failed -0.8518955 0.8518955 cpue
## 2 FISHERYEI 0.338 Passed -1.0819948 1.0819948 cpue
## 3 FISHERYGS 0.117 Passed -1.9741674 1.9741674 cpue
## 4 FISHERYJOIN 0.819 Passed -1.7833087 1.7833087 cpue
## 5 FISHERYSSIW 0.025 Failed -0.7378487 0.7378487 cpue
## 6 SURVEYBS 0.278 Passed -2.9025232 2.9025232 cpue
## 7 SURVEYEI 0.708 Passed -2.5243079 2.5243079 cpue
## 8 SURVEYGS 0.753 Passed -3.2945195 3.2945195 cpue
## 9 SURVEYJOIN 0.268 Passed -2.8038689 2.8038689 cpue
## 10 SURVEYSSIW NA Excluded NA NA cpue
## 11 PREDATOR 0.000 Failed -0.3745365 0.3745365 cpue
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERY 44.7 21
## 2 SURVEY1 82.6 24
## 3 PREDATOR 25.8 41
## 4 Combined 52.1 86
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 54.3 18
## 2 FISHERYEI 40.7 20
## 3 FISHERYGS 72.8 14
## 4 FISHERYJOIN 65.6 6
## 5 FISHERYSSIW 33.8 21
## 6 SURVEYBS 102.9 21
## 7 SURVEYEI 80.5 18
## 8 SURVEYGS 111.5 20
## 9 SURVEYJOIN 108.4 8
## 10 SURVEYSSIW 52.6 2
## 11 PREDATOR 39.4 41
## 12 Combined 71.3 189
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 54.3 18
## 2 FISHERYEI 40.4 20
## 3 FISHERYGS 73.1 14
## 4 FISHERYJOIN 64.1 6
## 5 FISHERYSSIW 33.8 21
## 6 SURVEYBS 103.3 21
## 7 SURVEYEI 81.3 18
## 8 SURVEYGS 111.8 20
## 9 SURVEYJOIN 108.5 8
## 10 SURVEYSSIW 53.3 2
## 11 PREDATOR 39.4 41
## 12 Combined 71.5 189
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 54.2 18
## 2 FISHERYEI 40.8 20
## 3 FISHERYGS 72.5 14
## 4 FISHERYJOIN 66.2 6
## 5 FISHERYSSIW 33.8 21
## 6 SURVEYBS 102.5 21
## 7 SURVEYEI 80.3 18
## 8 SURVEYGS 111.5 20
## 9 SURVEYJOIN 108.1 8
## 10 SURVEYSSIW 53.3 2
## 11 PREDATOR 39.4 41
## 12 Combined 71.2 189
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 55.4 18
## 2 FISHERYEI 39.6 20
## 3 FISHERYGS 75.5 14
## 4 FISHERYJOIN 59.8 6
## 5 FISHERYSSIW 34.0 21
## 6 SURVEYBS 106.4 21
## 7 SURVEYEI 82.7 18
## 8 SURVEYGS 112.4 20
## 9 SURVEYJOIN 110.8 8
## 10 SURVEYSSIW 47.1 2
## 11 PREDATOR 39.4 41
## 12 Combined 72.4 189
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 76.7 18
## 2 FISHERYEI 51.1 20
## 3 FISHERYGS 104.9 14
## 4 FISHERYJOIN 39.2 6
## 5 FISHERYSSIW 53.4 21
## 6 SURVEYBS 110.2 19
## 7 SURVEYEI 111.3 18
## 8 SURVEYGS 114.1 19
## 9 SURVEYJOIN 145.2 8
## 10 SURVEYSSIW 33.0 2
## 11 PREDATOR 39.4 41
## 12 Combined 84.2 186
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 63.7 18
## 2 FISHERYEI 43.0 20
## 3 FISHERYGS 89.0 14
## 4 FISHERYJOIN 38.2 6
## 5 FISHERYSSIW 41.3 21
## 6 SURVEYBS 108.8 20
## 7 SURVEYEI 96.8 18
## 8 SURVEYGS 123.7 20
## 9 SURVEYJOIN 125.4 8
## 10 SURVEYSSIW 11.0 2
## 11 PREDATOR 39.4 41
## 12 Combined 78.8 188
## Plotting JABBA residual plot
##
## RMSE stats by Index:
## indices RMSE.perc nobs
## 1 FISHERYBS 55.2 18
## 2 FISHERYEI 39.8 20
## 3 FISHERYGS 75.5 14
## 4 FISHERYJOIN 57.7 6
## 5 FISHERYSSIW 33.9 21
## 6 SURVEYBS 106.7 21
## 7 SURVEYEI 83.6 18
## 8 SURVEYGS 113.0 20
## 9 SURVEYJOIN 110.4 8
## 10 SURVEYSSIW 46.7 2
## 11 PREDATOR 24.5 41
## 12 Combined 71.2 189
Los análisis retrospectivo, dan cuenta de diferencias de estimación (sub - sobreestimación) en los patrones entre modelos evaluados.
Implementing the Hindcast Cross-Validation (HCxval) diagnostic in
Stock Synthesis requires the same model outputs generated by
r4ss:SS_doRetro(). As a robust measure of prediction skill,
we implemented the mean absolute scaled error (MASE). In brief, the MASE
score scales the mean absolute. Regarding (A MASE score > 1 indicates
that the average model forecasts are worse than a random walk.
Conversely, a MASE score of 0.5 indicates that the model forecasts twice
as accurately as a naïve baseline prediction; thus, the model has
prediction skill.
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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## starter.sso with Bratio: SSB/SSB0 and F: _abs_F
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another
0.0001 final convergence criteria (e.g. 1.0e-04)
comparision between select models No spatialand
Spatial implicit
comparision between select models Old Paramters and
New Parameters WG SAM 2024/23